MEDICARE PART D (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Segment Reporting Information [Line Items]
Other current assets	$ 5,393	$ 6,493
Trade accounts payable and accrued expenses	(5,787)	(4,509)
Other long-term assets	3,690	4,379
Other long-term liabilities	(1,907)	(2,383)
Risk Corridor Settlement
Segment Reporting Information [Line Items]
Other current assets	148	363
Trade accounts payable and accrued expenses	(93)	(68)
Net current asset (liability)	55	295
Other long-term assets	361	5
Other long-term liabilities	(212)	(194)
Net long-term asset (liability)	149	(189)
Total net asset (liability)	204	106
CMS Subsidies/ Discounts
Segment Reporting Information [Line Items]
Other current assets	703	1,894
Trade accounts payable and accrued expenses	(2,355)	(466)
Net current asset (liability)	(1,652)	1,428
Other long-term assets	0	0
Other long-term liabilities	0	0
Net long-term asset (liability)	0	0
Total net asset (liability)	$ (1,652)	$ 1,428